            class InputNumber{
                constructor(ops){
             
                    this.min = ops.min || 0;
                    this.max = ops.max || 100;
                    this.step = ops.step || 1;
                    this.value = ops.value || 0;
                    this.cont = ops.cont || document.createElement("div");
                    this.createDOM();
                }
                createDOM(){
                    this.reduce = document.createElement("span");
                    this.reduce.className = "reduce";
                    this.add = document.createElement("span");
                    this.add.className = "add";
                    this.ipt = document.createElement("input");
                    this.ipt.setAttribute("class", "ipt");
                    this.reduce.innerText = "-";
                    this.add.innerText = "+";
                    this.ipt.value = this.value;
                    this.cont.appendChild(this.reduce);
                    this.cont.appendChild(this.ipt);
                    this.cont.appendChild(this.add);
                    this.addEvent();
                }
                addEvent(){
                    const that = this;
                    this.reduce.addEventListener("click", function(){
                        let n = that.ipt.value-0;
                        if(n === that.min){
                            n = that.min;
                        }else{
                            n-=that.step;
                        }
                        that.ipt.value = n;
                    })
                    this.add.addEventListener("click", function(){
                        let n = that.ipt.value-0;
                        if(n === that.max){
                            n = that.max;
                        }else{
                            n+=that.step;
                        }
                        that.ipt.value = n;
                    })
                    this.ipt.addEventListener("input",function(){
                        const val = this.value;
                        let s = "";
                        for(let i=0;i<val.length;i++){
                            if(/\d/.test(val[i])){
                                s += val[i];
                            }
                        }
                        this.value = s;
                        if(val === "" || val <= that.min){
                            this.value = that.min;
                        }
                        if(val >= that.max){
                            this.value = that.max;
                        }
                    })
                }
            }

            new InputNumber({
                min: 1,
                max: 3,
                value: 1,
                cont: document.querySelector(".goods_datail_6_number")
            })  
 

